Thomas Leech, 19, believed conspiracy theories that the Jews were planning the “Great Replacement” of the white race through extinction and the “Islamicisation” of Europe, Manchester Crown Court heard.
The autistic youngster had become an isolated, lonely and vulnerable figure who rarely left his home and his far-right online activities “filled a void”, the court was told.
The court heard that after being arrested by counter-terrorism police, he told officers: “I am a Nazi.”
Police found he had posted online a “call to arms” for the white race, glorifying far-right killers, including Anders Breivik, who murdered 69 youngsters in Norway, and Brenton Tarrant, who murdered 51 people at mosques in Christchurch, New Zealand, in 2019.
Leech, of Derby Road, Preston, admitted at an earlier hearing three counts of encouraging acts of terrorism and two counts of stirring up religious or racial hatred, between March and November 2020.
He also admitted possessing indecent images of children.
Locking up the defendant for two years in a young offenders institute, Judge Alan Conrad QC said: “The offences you committed are deeply disturbing.”
Earlier Joe Allman, prosecuting, said Leech first came to police attention when he claimed to be planning a shooting at his school, Wetherby High School, in January 2017.
He told police it was a “prank” and received a caution and some intervention.
Leech was referred to Prevent, the Government’s deradicalisation programme, but he “dropped off the radar” when he moved to Gillingham, Kent, in June 2017.
After moving to Preston, Lancashire, in 2020, posts by him on the online platform called Gab, said to be popular amongst the far-right, were found by the Community Security Trust, a charity involved in security for Jewish communities.
Mr Allman said: “The cumulative effect of the posts is a call to arms by Mr Leech, inciting others who shared his world view to commit mass murder.
“They are replete with evidence of antisemitism.”
Leech posted that the Holocaust was a hoax, Jews controlled the world, Third Reich imagery and anti-Muslim content, the court heard.
Breivik and Tarrant, along with Robert Bowers, who murdered 11 people at a synagogue in Pittsburgh in 2018 and Dylann Roof, a white supremacist who murdered nine African-Americans at a church in Charleston in the US in 2015, were talked of in terms of martyrs to the white race, the court heard.
One post was a photo of Tarrant, sat in his car, smiling, just before he went on the rampage, with the words underneath: “What can one person do?”
The court heard there was no evidence Leech’s posts had inspired anyone to commit an offence.
Rachel White, mitigating, said some offences were committed when Leech was aged only 17 or 18 and that he suffered from autism, agoraphobia and bullying, which kept him out of school. She said he rarely left his home, spending his life online.
She added: “He effectively became a keyboard warrior. He was doing it because he needed a feeling of belonging and significance and literally had time on his hands.
“He is ashamed and embarrassed about what he has done.”